Ultimate Summer Achievements Here is the full list of all 16 Ultimate Summer achievements.Filter Achievement View View Image viewList view Sort by TrueSteamAchievement desc TrueSteamAchievement asc Achievement name desc Achievement name asc TSA Ratio desc TSA Ratio asc Gamers desc Gamers asc Steam order Date won desc Date won asc What are achievement flags? Click to find outApply Planet of the ApesFinish 1st mission HellraiserFinish 2nd mission From BeyondFinish 3rd mission El MaquinistaFinish 4th mission Apocalypse NowFinish 5th mission Mil gritos tiene la nocheFinish 6th mission In the Mouth of MadnessFinish 7th mission PossessionFinish 8th mission AnnihilationFinish 9th mission The ExorcistFinish 10th mission Invasion of the Body SnatchersFinish 11th mission War of the WorldsFinish 12th mission Prince of DarknessFinish 13th mission PhantasmFinish 14th mission BabeAchieve everything PsychoAchieve all the in-game achievements